The present invention relates to a multi-pole low-voltage power switch with a switching shaft shared by all poles, with pole units each assembled from at least two switching chambers, and with a drive apparatus shared by all pole units.
A power switch of this kind is known, for example, from German Patent Document No. DE-A-35 42 746. The construction of power switches evident from this and from other patent documents is theoretically usable for power switches with any rated current. It is known how to construct this kind of power switch for a very high rated currents, which can exceed 4000 A by combining subassemblies that are dimensioned for a low rated current. This applies in particular to the actual current-carrying parts, such as contact systems and arc quenching chambers. A power switch constructed in this fashion is described in European Patent Document No. EP-A-0 320 412.
One feature of the power switch that has been expanded in a modular fashion to a high rated current is its significantly enlarged width, in certain circumstances, as compared to versions for lower rated currents. This entails the problem that normal and otherwise inconsequential dimensional deviations in the assembled components are added together, which can impair the operation of the power switch or even interfere with its proper assembly. The underlying objective of the present invention is to eliminate difficulties which occur because of dimensional deviations, both when the components of the switch are assembled, and as the switch interacts with a pull-out rack.